What beer is making a phenomenal comeback after years of decline? Miller Lite!

What does all this mean? It means I've run out of excuses: it's time to talk about light beer.

My wife gets a lot of cooking magazines that are focused on lower-calorie eating, like Cooking Light and Weight Watchers (of course, while she's reading, I'm doing most of the cooking). These magazines often run a "recipe makeover," in which a delicious favorite dish, like Cheesy Bacon Ham Hock Surprise, is "slimmed down" in calories and fat, usually by taking out the meat and adding unsweetened applesauce. Yummy. The new dish still tastes great, we're told, but it's less filling.

Sound familiar? Of course it does! "Tastes great, less filling" are the words that sold America on light beer – Miller Lite. We sure didn't want the first light beer, Gablinger's, made by Rheingold. All it promised was that "It doesn't fill you up," without saying anything about the taste, and it leaned on the diet side of the equation. It bombed. No American guy wanted to say to the world, "Hey, I'm a fatso, I drink Gablinger's!"

The Gablinger's formula was created by a young brewing chemist named Dr. Joe Owades. Gablinger's was such a marketing disaster that Rheingold actually gave the formula to Chicago brewers Peter Hand Brewing. They brewed up the light beer and linked it to their flagship brand, calling it Meister Brau Lite. ("They did not spell right in Chicago," Owades told me last year, with the air of someone who's told the same dry joke for years and will probably tell it many more times.)

Meister Brau Lite saw some success, and when Phillip Morris went looking for ways to build their investment in Miller Brewing, that's what they found. They bought Meisty Lite and the formula, re-branded it as Miller Lite, and away they went, with extravagant, hilarious ads ("Tastes Great! Less Filling!") filled with popular sports celebrities that literally changed the face of American brewing. (That's a clip from one of the ads right there.) Light beer is a phenomenal success, probably the most successful thing that's ever hit American brewing.

"It took Miller to make light beer," Owades said, "because at Phillip Morris, they weren't beer people. They didn't care about beer – they just wanted a new market. They were the only ones that would do that."

But what is light beer? A "light beer" is defined legally as one that has 20 percent or more fewer calories than a brewery's "regular" beer. Fewer calories don't just happen, they have to come from somewhere.

Largely they come from less alcohol – light beers run roughly half a percentage point lower in alcohol – and less "body." Beer's body comes from proteins and unfermentable sugars. Light beers deal with the unfermentable sugars in one way or another, through various proprietary means. Some involve messing with the mash (the grain gruel from which beer is made), some involve "super yeasts" that eat up more of the fermentable sugars, and some just add less "fuel," (i.e., less malt and adjuncts).

Owades tells of his eureka moment in terms that sound very familiar today. "I realized that beer had carbohydrates it didn't need to have," he said. "The only reason it had carbs was because the way of making it then didn't get rid of the excess carbs. I found a way to do it."

There's also the simple method of watering down the beer. If that sounds objectionable, it's not, not any more than with any other beer. Almost every mainstream beer in the United States is produced by what's known as "high gravity" brewing. A brewer can save serious money by brewing beer at a higher alcohol content and carefully diluting it later.

How does that work? Brewers add a calculated extra amount of malt, rice, corn, whatever "fuel" is used, to boost the beer to 6.5 percent alcohol by volume (ABV) or higher. Once the fermented beer has been filtered, water is added to bring the ABV down to the target level of between 4 and 5 percent. This saves energy and labor costs during the brewing process by effectively squeezing 1,300 barrels of beer into a 1,000-barrel brewkettle (a barrel is 31 gallons). While only 1,000 barrels are boiled, 1,300 barrels are eventually bottled. It also saves money by allowing more efficient use of fermentation tank space: 10,000-barrel fermenters produce 13,000 barrels of beer.

If that doesn't sound like that big a deal, realize that the Anheuser-Busch plant in Baldwinsville, N.Y., makes four 1,000 barrel batches simultaneously, several times a day, and puts out 8 million barrels of beer a year (that's the equivalent of more than 99 million cases). High-gravity brewing, in other words, creates some serious cost savings.

There's nothing wrong with this process; it's been used for decades. Chances are, every mainstream beer you've ever had was brewed this way. (And you beer geeks, stop laughing: there are British brewers who swear that this is why IPA was brewed stronger and hoppier – so it could be shipped cheaper to India, and then diluted with boiled water once it arrived.) You can see how it could easily be manipulated to produce a beer with lower alcohol and lower body by adding a little more water. It's not really "watered down" beer. It's just been processed a bit more.

Now that you know about how light beer is made, think about it. Is it that different from what you suspected, when you even bothered to think about it? If you were sitting on the deck, relaxing with a cold light beer with your friends or your spouse, and one of you happened to muse, "Wonder how they make light beer, anyway?" didn't you probably figure it was something like that, using less stuff, taking something out, or adding water? Bet it didn't put a crimp in your enjoyment. After all, it tasted the same before and after the conversation.

Light beer is popular not because of how it's made, but because it delivers on its promise of "lightness." Light beer does have fewer calories than premium beer; maybe not that many fewer, but fewer. It does have less alcohol, so it won't impair you as quickly as premium beer. (So does Guinness Stout, but that's a whole other story.) And if it tastes a little less robust, well, premium beer isn't exactly overwhelming in the taste category anyway. What the hell, who cares? Open another.